It is necessary when installing a railway track to carry out length adjustments of the rails which will be laid by cutting the rails. Moreover during the repair of a railway track, it is sometimes necessary, if some railway track sections are damaged, to cut out the damaged portions for replacing them with new portions.
The cutting of the rails is carried out with a cutting machine generally comprising a heat engine driving a grinding wheel which will carry out the cutting work.
The subject of the invention is a cutting machine comprising an engine block associated with a grinding wheel rotatably driven thereby and mounted on a support used for guiding in the plane of the grinding wheel and pivoting transversely with respect to the metal part while being pivotally mounted onto a vise intended to be fastened onto the metal part, wherein the grinding wheel is mounted at one end of an arm connected with its other end to the engine block.
An apparatus of this kind was already known in particular from the publication No 2,267,418 of the French patent No 74 12 377 relating to a cutting machine fitted with an engine block and with a support to be fastened onto a rail to be cut through the medium of a vise. The support of the cutting machine consists of two arms having substantially the same length and pivotally connected to each other and, at their other ends, to the cutting machine and to the vise, respectively, at a point located substantially above the rail. These pivotally connected arms provide good guiding of the grinding wheel in a transverse plane perpendicular to the rail to be cut. However the operator is in an uncomfortable working position because the cutting machine is very close to the ground and because he carries the cutting machine while causing it to move with respect to the rail for avoiding stalling the engine, which phenomenon would occur if the grinding wheel remained in a same position with respect to the rail. Since indeed the engine of the cutting machine has limited power, it is necessary that the contact surface between the grinding wheel and the rail be as small as possible to avoid engine labouring and to ensure effective cutting. The operator therefore is in an inconvenient position and in a zone in which he undergoes the harmful effects or nuisances of the smoke of the heat engine and of the sparks which result from the cutting operation. Moreover when the rail has been cut partially on one side thereof, it is necessary to stop the cutting operation, to disconnect the engine block from the pivotally connected arms, removing it from its support, to tilt or swing the support to the other side of the rail, to pivot the engine block by 180.degree. about a vertical axis located in the plane of the grinding wheel and passing through its centre for pivoting the engine block about this vertical axis and to mount again the engine block back onto the pivotally connected arms forming the support on the same initial side thereof in order to be able to carry out the second part of the cutting operation for completing it. Thus during the first phase of the cutting operation, the engine block is located, with respect to the plane of the grinding wheel, on that side of this plane which is opposite to the side where the vise is located and the aforesaid turning up causes the engine block to pass on the other side of the plane, i.e., on the side where the vise is located.